National Pesticides Monitoring and Surveillance Network

Program Overview

Little AuSable River in Southwestern Ontarioriver during the early spring

Canadian’s are universally concerned about the quality of our water resources. Pesticides have been identified as one of the fifteen key threats (Threats to Sources of Drinking Water and Aquatic Ecosystem Health in Canada) to Canadians freshwater quality, with a National pesticides surveillance and monitoring program identified as a key need. The National Pesticides Monitoring and Surveillance Network was established in 2003 to study, evaluate and report on pesticides and their transformation products to support Environment Canada’s freshwater ecosystem approach to watershed management. The Program also generates relevant data, information and advice that are considered by the Pesticide Management Regulatory Agency in carrying out its regulatory mandate for pest control products under the Pest Control Products Act.

The Network operates on a rotational basis in high risk priority watersheds, and focuses on:

current-use pesticides undergoing risk assessment;

pesticides those that have been the subject of risk management decisions; as well as,

selected current-use pesticides of emerging concern.

The Network is designed to be flexible, allowing for changes to site selection, parameters measured, and frequency of sampling as program results are evaluated and regulatory needs redefined.

The Program provides comprehensive, systematic and detailed information on an agreed-upon list of current-use pesticides from a national perspective, complemented by information on additional, specific pesticides of interest in selected watersheds.

During the 2010 sampling season there were twenty sites in the National Pesticides Monitoring and Surveillance Network (including five reference sites), strategically located in key watersheds across Canada (see map).

The herbicides 2,4-D, mecoprop, dicamba, glyphosate and its major metabolite AMPA were most frequently detected. Using either herbicide concentrations upstream/downstream of urban centres or bromoxnil and clopyralid as surrogates for agricultural input of herbicides to streams, it was clear that environmental levels of these herbicides in urban areas were closely linked to urban use in Canada. None of the herbicides measured exceeded existing guidelines for the protection of aquatic life.

This is the first time a national survey of pesticides in urban rivers has been carried out in a consistent fashion across the country. Although it was determined that 2,4-D, mecoprop, dicamba, glyphosate and AMPA were frequently detected and linked to urban use there were some geographical differences suggesting differences in usage patterns. Some jurisdictions in Canada have recently restricted cosmetic use of pesticides and such restrictions may lead to reduced pesticide concentrations in surface waters.